GRAPP & IVAPP 2012: Proceedings of the International Conference on Computer Graphics Theory and Applications and International Conference on Information Visualization Theory and Applications

This book contains the proceedings of the International Conference on Computer Graphics Theory and Applications (GRAPP 2012) and of the International Conference on Information Visualization Theory and Applications (IVAPP 2011) which were organized and sponsored by the Institute for Systems and Technologies of Information, Control and Communication (INSTICC). We hope that the proceedings here published, demonstrate new and innovative solutions, and highlight technical problems in each field that are challenging and worthwhile. Thus, GRAPP and IVAPP were organized to promote a discussion forum between researchers, developers, manufactures and end-users, about the conferences research topics and to establish guidelines in the developing of more advanced solutions. We received a high number of paper submissions for this edition of GRAPP, 116 in total, with contributions from all five continents which attest to the success and global dimension of GRAPP. To evaluate each submission, we used a double-blind evaluation method and each paper was reviewed by at least two experts from the International Program Committee. In the end, 20 papers were selected for publication as full papers, 35 papers were accepted for short presentation and 23 were accepted for poster presentation. The result was an oral-paper acceptance ratio of 47% and a high-quality program that is attractive to experts from Computer Graphics area. A high number of paper submissions for this edition of IVAPP was also received, 66 in total, with contributions from all five continents which attest to the success and global dimension of IVAPP. 12 papers were selected for publication as full papers, 7 papers were accepted for short presentation and 15 were accepted for poster presentation. The result was an oral-paper acceptance ratio of 29% and a high-quality program that is attractive to experts from Information Visualization area. We hope that these Conference Proceedings, submitted for indexation by Thomson Reuters Conference Proceedings Citation Index, INSPEC, DBLP and EI, may help the Computer Graphics community to find interesting research work. Furthermore, a short list of presented papers will be selected to be expanded into a forthcoming book of VISIGRAPP Selected Papers to be published by Springer during 2012. Moreover, the conference also featured a number of keynote lectures delivered by internationally well known experts thus contributing to increase the overall quality of the conference and to provide a deeper understanding of the conference interest fields. In order to promote the development of professional networks the organizing committee has prepared a Conference Dinner in the evening of February 25th. We hope that you enjoy this exciting conference and have an unforgettable stay in the beautiful city of Rome, Italy. Finally, we would like to express our thanks, first of all, to the authors of the technical papers, whose work and dedication make possible to put together a program that we believe very exciting and of high technical quality. Next, we would like to thank all the members of the program committee and auxiliary reviewers, who helped us with their expertise and time. We would also like to thank the invited speakers for their invaluable contribution and for sharing their vision in their talks. Special thanks should be addressed to the INSTICC Steering Committee whose invaluable work made possible this event. We wish you all an exciting conference and an unforgettable stay in Rome, Italy. We hope to meet you again for the next edition of GRAPP and IVAPP, details of which will be shortly available at http://www.grapp.visigrapp.org and http://www.ivapp.visigrapp.org

EHR STAR: The State‐Of‐the‐Art in Interactive EHR Visualization

Since the inception of electronic health records (EHR) and population health records (PopHR), the volume of archived digital health records is growing rapidly. Large volumes of heterogeneous health records require advanced visualization and visual analytics systems to uncover valuable insight buried in complex databases. As a vibrant sub-field of information visualization and visual analytics, many interactive EHR and PopHR visualization (EHR Vis) systems have been proposed, developed, and evaluated by clinicians to support effective clinical analysis and decision making. We present the state-of-the-art (STAR) of EHR Vis literature and open access healthcare data sources and provide an up-to-date overview on this important topic. We identify trends and challenges in the field, introduce novel literature and data classifications, and incorporate a popular medical terminology standard called the Unified Medical Language System (UMLS). We provide a curated list of electronic and population healthcare data sources and open access datasets as a resource for potential researchers, in order to address one of the main challenges in this field. We classify the literature based on multidisciplinary research themes stemming from reoccurring topics. The survey provides a valuable overview of EHR Vis revealing both mature areas and potential future multidisciplinary research directions

Foreword to special issue on knowledge assisted visualization

No abstract

Smooth Graphs for Visual Exploration of Higher-Order State Transitions

In this paper, we present a new visual way of exploring state sequences in large observational time-series. A key advantage of our method is that it can directly visualize higher-order state transitions. A standard first order state transition is a sequence of two states that are linked by a transition. A higher-order state transition is a sequence of three or more states where the sequence of participating states are linked together by consecutive first order state transitions. Our method extends the current state-graph exploration methods by employing a two dimensional graph, in which higher-order state transitions are visualized as curved lines. All transitions are bundled into thick splines, so that the thickness of an edge represents the frequency of instances. The bundling between two states takes into account the state transitions before and after the transition. This is done in such a way that it forms a continuous representation in which any subsequence of the timeseries is represented by a continuous smooth line. The edge bundles in these graphs can be explored interactively through our incremental selection algorithm. We demonstrate our method with an application in exploring labeled time-series data from a biological survey, where a clustering has assigned a single label to the data at each time-point. In these sequences, a large number of cyclic patterns occur, which in turn are linked to specific activities. We demonstrate how our method helps to find these cycles, and how the interactive selection process helps to find and investigate activities.MediamaticsElectrical Engineering, Mathematics and Computer Scienc

Simplification of Morse Decompositions using Morse Set Mergers

Abstract. A common problem of vector field topology algorithms is the large number of the resulting topological features. This paper describes a method to simplify Morse decompositions by iteratively merging pairs of Morse sets that are adjacent in the Morse Connection Graph (MCG). When Morse sets A and B are merged, they are replaced by a single Morse set, that can be thought of as the union of A, B and all trajectories connecting A and B. Pairs of Morse sets to be merged can be picked based on a variety of criteria. For example, one can allow only pairs whose merger results in a topologically simple Morse set to be selected, and give preference to mergers leading to small Morse sets.